Inside of Hard Drive
                                                         

                                       -Most computer hard drives are in an internal drive bay at the front of the computer
                                        and connect to the motherboard using either ATA,SCSI or a SATA cable and power cable.
                       -Below, is an illustration of what the inside of a hard drive looks like for a desktop andlaptop hard drive.
                        
                                            

       HARD DISK DRIVE 

-Hard disk drive is abbreviated as HD or HDD, the hard drive is the computer's main storage media device that permanently stores all data on the computer.

-The hard drive was first introduced on September 13, 1956 and consists of one or more hard drive platters inside of air sealed casing. 
       

          · How is data read and stored on a hard drive?

Data sent to and from the hard drive is interpreted by the disk controller, which tells the hard drive what to do and how to move the components within the drive.When the operating system needs to read or write information, it examines the hard drives File Allocation Table (FAT) to determine file location and available areas. Once this has been determined, the disk controller instructs the actuator to move the read/write arm and align the read/write head.

       · External and Internal hard drives

Although most hard drives are internal hard drives, many users also use external hard drives to backup data on their computer and expand the total amount of space available to them. External drives are often stored in an enclosure that helps protect the drive and allow it to interface with the computer, usually overUSB or eSATA. A great example of a backup external device that supports multiple hard drives is the Drobo. 



                                                                            
                                                                                            

                                                                         Hard Disk Drive - 3D Visualization

                                    In this video you can see the Hard Disk Drive in three dimensions. 

Basic Hard Disk Drive Components

Many types of hard disks are on the market, but nearly all drives share the same basic physical components. Some differences may exist in the implementation of these components (and in the quality of materials used to make them), but the operational characteristics of most drives are similar. Following are the components of a typical hard disk drive (See the image in the lynk):

•  Disk platters

•  Logic board

•  Read/write heads

•  Cables and connectors

•  Head actuator mechanism

•  Configuration items (such as jumpers or switches)

•  Spindle motor

•  Bezel (optional)

  HERE YOU CAN SEE THE IMAGE:  http://alasir.com/books/hards/01-01.png

Internal lynk.  http://www.geocities.ws/spainmanulovers/index.html